Omg, you all misunderstand. ITS NOT THE WEAPON, ITS THE YANG MAGIC!!!
I use Light Magic empowered by my divine protection to boost my NORMAL weapon.
Why can I make a light sword if I only have the hilt? Because the hilt is made of pure gold so I use the gold inside the hilt to also* activate my divine protection and empower my magic further, hence the [s]lightsaber[/s] plasma sword.